Catheter adapted for fluid connection prior to insertion



Oct. 28, 1969 R. G. SPADEMAN 3,474,735

CATHETER ADAPTED FOR FLUID CONNECTION PRIOR TO INSBRTION *1 Filed Dec. 4. 1968 2 Sheets-Sheet l 60 w I 9 5; 62; a! w w INVENTOR.

(Qt-hard nivademcm Y ATTOR EY:

R. G. SPADEMAN CATHETER ADAPTED FOR FLUID CONNECTION PRIOR TO INSERTION Oct. 28. 1969 2 Sheets-Sheet 2 Filed Dec. 4, 1968 INVENTOR. Richard 6. Spddlndtt United States Patent Int. Cl. A61m 5/00 US. Cl. 128-2144 6 Claims ABSTRACT OF THE DISCLOSURE A catheter of the type comprising a hollow body with a hub portion at the outer end and a trocar portion at the inner end for piercing insertion into a patient, and an elongated flexible tube slidably extending through the trocar portion and into the patient. An enlarged plug is secured on an outwardly extending portion of the flexible tube and is adapted to be seated in a recess in the hub portion when the tube is fully inserted into the patient. The plug has a vent passage communicating with the tube to permit release of air in the tube when inserted into the patient and to permit the flow of fluid for indicating proper insertion of the tube. The outer end of the vent passage is positioned in the recess when the plug is seated in order to prevent leakage of fluid from the plug. Provision is made for connecting fluid communicating apparatus prior to the insertion of the trocar portion into the patient. In one embodiment the fluid is communicated through a passageway in the hub portion which registers with the vent passage of the plug when the plug is seated; and in another embodiment the fluid is communicated through the rear end of the plug. By arranging the portion of the flexible tube extending into the hollow body to be of greater length than the portion of the tube extending outwardly from the body, the sterility of the portion of the tube insertable into the patient may be maintained without the necessity of a surrounding sack.

This application is a continuation-in-part of application Ser. No. 552,891, filed May 25, 1966, now abandoned.

This invention relates to catheters, and more particularly to a catheter having integral connection means to permit connection to fluid-communicating apparatus without unnecessary harm of discomfort to the patient.

In many types of medical treatment it is necessary to communicate fluids of one sort or another directly into or out of the body vessels or cavities of the patient. For sake of illustration, consider the infusion of fluids into the vascular system of the patient. The normal practice under such circumstances is to pierce the skin and vascular wall with a catheter device, locate the catheter within the vascular channel and administer fluids through the catheter to the vascular channel. Under certain circumstances, the required medical treatment takes place over an extended period of time, making it necessary to either leave the catheter in place for such length of time, or to remove the catheter and repuncture the vascular wall as necessary. Obviously, the latter method is unsatisfactory since continued punctures of the vascular channel tend to cause venous thrombosis, subcutaneous haematomas, and otherwise considerable discomfort to the patient. If the catheter is left in place over the extended period of time, it is necessary to prevent, as much as possible, relative movement between the catheter and the limb of the patient into which the catheter extends for minimum discomfort to the patient.

Heretofore, such intravascular catheters have included rigid needles, used to puncture the skin and vascular wall and remain in the vascular channel. Since such devices are of a rigid nature, they cannot adjust to the contour of the vascular wall or the vascular channel, nor can they compensate for movement of the limb of the patient with which the catheter is used. Such movements and such variations in wall contour tend to cause punctures and/ or inflammation of the vascular wall, leading to leakage of vascular fluids to the extravascular tissue. To avoid these problems it is becoming more and more popular to use flexible tubes of some sort which are extended into the vascular channel and which are of sufiicient resilience to conform to the vascular wall and prevent such punctures.

With presently available flexible catheters, a sharpened trocar, or stylet, is normally used to puncture the skin and vascular wall, the trocar being disposed within a flexible tube which passes through the vascular wall with the trocar. The trocar may then be removed from the catheter, leaving the tube within the channel, and suitable infusion apparatus is attached. Heretofore, devices of this nature have required complete removal of the trocar from the catheter and then connection to the infusion apparatus for the desired purpose. This process causes considerable difliculty and has numerous disadvantages. By first removing the trocar and then connecting the infusion equipment, there is a loss of vascular fluid through the catheter, making it a rather messy operation. The possibilities of contamination are increased and the possibility of admitting air to the catheter, and thus to the vascular channel is increased. Furthermore, there is considerable discomfort to the patient when the infusion apparatus is attached, since it is practically impossible to hold the catheter in a completely stationary position for attachment of the infusion apparatus.

The device in which this invention is embodied comprises, generally, a catheter of the flexible type and including a body having a hub portion and a sharpened trocar portion, the body having a bore formed therethrough to slidingly receive a flexible or resilient tube that ultimately conveys the fluid. The sharpened end of the trocar portion is suitable, for example, for puncturing the skin and the vascular wall for insertion into the vascular channel. The resilient tube may then be passed through the hub portion and trocar portion into the vascular channel, at which point the rigid body and trocar portion are removed from the vascular channel. The infusion apparatus is connected to the catheter prior to the insertion of the trocar portion into the vascular channel. Immediately upon removal of the trocar portion, the infusion operation can begin and there is no need to disconnect any part of the catheter for connection of the infusion apparatus. The rearward end of the flexible tube is provided with an enlarged plug, sealingly receivable in the hub portion of the body, the plug being provided with a passage communicating with the opening in the tube to permit the release of air from the tube as the vascular fluid backs up in the tube. The sealing engagement of the plug within the hub portion closes off the vent passage so that during the infusion operation there is no leakage of infusion fluid. In order to protect the sterility of the catheter, a flexible or pliable plastic sack may be secured to the hub portion of the body to enclose the outwardly projecting tube portion and the enlarged plug. The sack is of such a nature as to permit the movement of the tube relative to the body by manipulation through the sack and without requiring removal of the sack to carry out the operation of the catheter.

A device of this nature overcomes many disadvantages heretofore found in catheters. With particular reference to intravascular catheters, the flexible tube permits the catheter to conform to the contour of the vascular wall and the vascular channel, without additionally puncturing the vascular wall or causing discomfort within the vascular channel in the limb or other portion of the body with which the catheter is used. Since the infusion apparatus is integrally connected to the catheter prior to insertion into the vascular channel, the loss of vascular fluid is avoided and the entire device and operation is free of contamination. It is also relatively impossible to admit air into the vascular channel during the otherwise necessary connection of the infusion apparatus, and the discomfort to the patient is minimized since the catheter need not be touched once the trocar portion is retracted.

These and other advantages will become more apparent from the following description and drawing in which:

FIGURE 1 is a view with parts broken away and in section of a vascular channel with a catheter embodying the present invention being inserted therein;

FIGURE 2 is a view similar to FIGURE 1 showing the catheter with the trocar portion removed from the vascular channel;

FIGURE 3 is an elevational view, with parts broken away and in section, of the embodiment of the catheter illustrated in FIGURES 1 and 2, showing the catheter in condition for insertion into a patient;

FIGURE 4 is an elevational view, with parts broken away and in section, illustrating another embodiment of a catheter in accordance with the present invention, in condition for insertion into a patient;

FIGURE 5 is an elevational view, with parts broken away and in section, of another embodiment of a catheter in accordance with the present invention showing the catheter in condition for insertion into a patient;

FIGURE 6 is an elevational view of a modified form of the catheter illustrated in FIGURE 5, showing the catheter in condition for insertion into a patient;

FIGURE 7 is an elevational sectional view of the catheter of FIGURE 6, also showing the catheter in condition for insertion into a patient;

FIGURE 8 is an elevational sectional view of the catheter of FIGURE 6, showing the catheter in the position assumed after insertion into a patient; and

FIGURE 9 is a fragmentary elevational view of a modification of the catheter of FIGURE 6, shown in the position assumed after insertion into a patient.

Referring more particularly to the drawings, FIGURES l and 2 best illustrate the use of an intravascular catheter in accordance with the present invention, and its manner of insertion into the vascular channel. In these figures, a limb or other portion of a body, illustrated generally by the numeral 10, is shown to include a vascular channel 12, surrounded by a wall 14, disposed within the extravascular tissue 16 and covered by a layer of skin 18. The vascular channel may be located anywhere within the body of the individual and may be a vein, artery or some other fluid carrying channel.

When it is necessary to administer a fluid to the vascular channel, for example, when it is necessary to feed a patient by the intravenous method, a catheter, illustrated generally by the numeral 20, may be used. The catheter is made to pierce the skin 18 and the vascular wall 14, as will become hereinafter more apparent, so that the end of the catheter 20 may be disposed within the vascular channel 12. The infusion apparatus permits the ingress of the desired fluid to the vascular channel to accomplish the desired result.

Referring now to FIGURE 3, the intravascular catheter 20 is shown to include a body, indicated generally by the numeral 22, including a hub portion 24, of any suitable configuration, and a trocar portion 26, preferably of narrow cylindrical shape terminating in a sharpened end 28. A bore 30 extends through the trocar portion 26 and a portion of the hub 24 and terminates in an enlarged recess 32 opening rearwardly of the hub portion 24. Extending outwardly from the hub portion 24 is a boss 34 having a passage 36 formed therein and communicating with the enlarged recess 32, and thus with the passage 30 in the trocar portion 26. Secured on the boss 34 in any suitable manner is a tube 38, forming an integral portion of the infusion apparatus and through which the infusion fluid passes to the catheter 29.

Received within the bore 30 in the trocar portion 26 and the hub portion 24, and extending rearwardly of the hub portion 24, is a flexible plastic tube, indicated generally by the numeral 40. Tube 40 is slidable within the bore 30 and includes a central passage 42 through which the infusion fluid is directed, as will become hereinafter more apparent. A portion of the tube is disposed within the trocar portion 26, and best illustrated in FIGURE 3, and a second portion of the tube 40 extends rearwardly from the hub portion 24, terminating in an enlarged plug, indicated generally by the numeral 44. Plug 44 is of any suitable shape and corresponds with the shape of recess 32 formed in the hub portion 24. It is preferred that the recess 32 and the shape of the plug 44 be conical, as illustrated in the drawing, and it is intended that the plug be sealingly received in the recess 32 when the catheter is installed in the vascular channel. Formed in the plug 44 is a cross passage 46 that communicates that the inner channel 42 of the tube 40. Passage 46 registers with the passage 36 in the boss 34 and hub 24 of the body 22 when the tube is passed through the bore 30 in the body 22. Thus, there is communication between the infusion apparatus 38 and the interior passage 42 in the tube 40. During the insertion of the plastic tube 40 into the vascular channel 12, passage 46 in the plug 44 permits the release of air within the passage 42 in the tube 40. At the same time, passages 42 and 46 permit a certain amount of flow through the tube 40 from the vascular channel to indicate proper seating of the tube within the vascular channel. Upon receipt of the enlarged plug 44 in the recess 32, and communication between the passage 36 and the passage 46 in the plug 44, the infusion fluid will go directly into the vascular channel and will not leak past the plug 44.

In order to protect the rearwardly extending portion of the tube 40 and the plug 44 from contamination, a flexible or pliable sack, indicated generally by the numeral 48, is suitably secured to the hub portion 24 of the body 22, and encloses the rearwardly extending portion of the tube 40 and plug 44. The sack 48 is intended to be of a clear plastic material and of suflicient flexibility to permit manipulation of the tube 40 and plug 44 relative to the body 22.

Referring now to FIGURE 4, a modification of the above described catheter is illustrated and which includes a body, indicated generally by the numeral 52, having a hub portion 54, of any desired configuration, and a trocar portion 56 of thin cylindrical shape terminating in a sharypened end 58-. A bore 60 extends through the trocar portion 56 and into the hub portion 54, terminating in an enlarged recess 62 opening rearwardly of the hub portion 54.

Extending through the body 52 and slidably movable in the bore 60 is a resilient or flexible tube, indicated generally by the numeral 64, having a passage 66 therein and having an enlarged plug, indicated generally by the numeral 68 adjacent the end thereof. Plug 68 corresponds in shape to the recess 62 in the hub portion 54 for sealing purposes as above described. A cross bore 70 is formed in the plug 68 and communicates with the interior passage 66 of the tube 64.

Surrounding the exposed end of the tube 64 is a flexible or pliable sack, indicated generally by the numeral 72, to protect the tube and plug 68 from contamination, the sack 72 being suitably secured to the hub 54. The rearward end of sack 72 may be bonded or otherwise adhered to the rear face 74 of the plug 68, and the sack includes an opening 76 through which extends an extension 78 on the tube 64. Extension 78 may be an integral part of tube 64 or may be a separate tubular member altogether. Se-

cured on extension 78 in any suitable manner is a tube 80, forming an integral part of the infusion apparatus, to permit fluid communication between the infusion apparatus and the interior passage 66 of the tube 64.

Referring next to FIGURE 5, yet another embodiment of a catheter is illustrated and which is similar to the embodiment illustrated in FIGURE 4. Like reference numerals indicate like parts. In the modification illustrated in FIGURE 5, the dimensions of the tube 82 become important. In this embodiment the forward portion 84 of the tube 82, being that part of the tube 82 extending through the trocar portion 56 from the inner end of the recess 62, is greater in length than the rearward portion 86 of the tube 82, being that portion of the tube 82 extending rearwardly from the forward part of the recess 62. By so forming the dimensions of the two portions of the tube, it will be apparent that the sack may be eliminated and that the portion of the tube 84 within the trocar portion 56 and hub 54 will be protected from contamination by being located within the trocar portion 56. Thus, when the catheter is mounted in the vascular channel the rearward portion 86 of the tube 82 will not come in contact with the vascular channel, or the tissue surrounding it, but will be retained within the trocar portion.

The operation of the structures illustrated in FIGURES 3, 4 and 5 are basically the same and may be described with reference to FIGURES 1 and 2. As illustrated in FIGURE 1, and with reference to its application as an intravascular catheter, the parts of the catheter 20' are so disposed that the tube 40 extends rearwardly from the body 22 and the trocar portion 26 may be caused to pierce the skin 18 and wall 14 of the vascular channel. Once the trocar is so inserted, the plastic tube 40 is manipulated forwardly through the body 22 and trocar portion 26, and the body 22 and trocar portion 26 are withdrawn from the vascular channel 12. Upon complete withdrawal of the trocar portion 26 the enlarged plug 44 will be sealingly engaged in the recess 32 in the hub portion 24 with the vent passage 46 in communication with the infusion passage 36 in the boss 34. It will be seen that the forward portion of the tube 40, being the only portion of the catheter 20 disposed within the vascular channel 12, is of sufficient flexibility to avoid discomfort to the patient with inadvertent movement of the catheter 20 relative to the limb or portion of the body with which it is used. The infusion of fluid through the infusion apparatus 38 and the passages 36-46-42 can now take place and such infusion can be intermittent or continued without requiring removal, replacement and/or adjustment of the flexible tube 40 within the vascular channel 12. During the insertion of the flexible tube 40 into the vascular channel 12, the vent passage 46 in the plug 44 permits the venting of any air disposed within the passage 42 of the tube 40. At the same time, natural reverse flow of the vascular fluid from the channel 12 through the passage 42 to the vent passage 46 will provide a visual indication of the proper setting of the tube 40 in the vascular channel 12.

The modifications illustrated in FIGURES 4 and 5 operate as intravascular catheters in substantially the same manner, the difference being in the location of the infusion apparatu 80, and its connection to the flexible tube 64. It will be apparent that upon sliding movement of the tube 64 or 82 relative to the body 52, the vent passage 70 in the enlarged plug 68 will be sealed upon proper receipt in the recess 62 in the hub portion 54. Infusion through the tube 64 or 82 is thus accomplished without leakage.

Thus, an intravascular catheter device is provided Which avoids the discomfort to the patient normally found in presently available catheters. The possibilities of contamination are greatly decreased, and the possibilities of ingress of air to the vascular channel is greatly reduced. The resulting operation is much safer and much more comfortable for the patient, since the catheter need not be moved once it is properly located, and continued punctures are not required in order to complete the necessary infusion operation.

A modification of the embodiment of FIGURE 5 is shown in FIGURES 6, 7 and 8. The significant concept disclosed with reference to FIGURE 5 is that by arranging the forward portion 84 of the catheter tube 82, which is covered by the body 52 in a sterility-maintaining manner, to be longer than the rearward portion 86, which is uncovered and exposed to unsterile conditions, sterility may be maintained without the necessity of a surrounding sack. In the modification of FIGURES 6, 7 and 8, a body construction is disclosed in which the sterility-maintaining covering length is increased, thereby increasing the length of the catheter portion 84 which is insertible into the patient as may be required in certain applications.

In FIGURES 6, 7 and 8, the trocar needle 56 is attached to a hub member 54' of standard configuration. A tubular member 90, which may, for example, be made of a flexible plastic material, fits over the end of the member 54' to provide a rearward hub extension to the body 52. A hollow tapered plug 68 is attached to the rear of the catheter tube 82 and contains a vent passage 70'. A tapered cavity or recess 62 is formed in the rear of the tubular member 90, such that the plug 68' may seat in the recess 62', as shown in FIGURE 8, and close off the vent passage 70. A connecting tube leading to external apparatus, such as infusion apparatus, is attached to a sealing lip 68" at the rear of the plug 68 (see FIGURE 7). Alternatively, a plug such as 68 in FIGURE 5 may be provided in which the catheter tube 82 connects directly to the external tube 80, the configuration of FIGURE 7 being generally useful for a large diameter tube 80 and the configuration of FIGURE 5 being generally useful for a small diameter tube 80. To facilitate connection, the end of the tube 80 maybe provided with a plug which fits over the plug 68' in male-female relationship.

The catheter is prepared for use in the position shown in FIGURES 6 and 7. The body 52, which covers and rniantains the sterility of the front portion 84 of the catheter tube over a distance A, consists of the trocar portion 56 and the hub portion comprising the hub member 54' and the hub extension 90. An enlarged bead 82' is positioned on the catheter tube 82 at the distance A from the front end in order to prevent contammatlon to the tube portion 84 caused by the accidental withdrawal of said tube portion from the body 52. In use, the trocar 56 is piercingly inserted into the patient and the catheter tube 82 is then slid through the body 52 until the plug 68' is seated in the recess 62' as shown in FIG- URE 8, whereupon a length of the front portion 84 of the catheter tube extends beyond the trocar 56 and into the patient. This insertable length may be made as long as desired by increasing the length of the hub extension and hence the sterilized distance A.

A simplified form of the catheter of FIGURE 6 results from use of the modification shown in FIGURE 9. The hub extension tube 90 is formed from a uniform piece of flexible plastic tubing (without the formation of separate cavity section such as 62' in FIGURE 8). The rear end of the tube 90 provides the recess 62" for the plug 68'. In view of the tapered configuration of the plug 68' and the resilient characteristics of the tube 90, a fluid-sealing friction fit is provided between these two parts when the catheter tube 82 is inserted into the patient. In this modifiaction, the head 82' is omitted from the catheter tube since no structure is provided for engaging said bead to prevent withdrawal (as shown in FIGURE 7). To prevent inadvertent excessive withdrawa'l of the catheter tube 82, said tube is made sufficiently wide to form a friction fit with the interior of the trocar 56. A visible mark may be placed on the tube 82 in place of the head 82' so that the user views said mark through the tube 90 (made of transparent material) and will stop withdrawal of the tube 90 when said mark reaches a reference position at the rear of the tube 90.

Although the foregoing has been primarily described with respect to infusion of the fliuds into the vascular channel, it is obvious that the reverse is also possible. That is, the catheter may be inserted into the vascular channel for removal of fluids therefrom, the setting of the catheter in the vascular channel for such removal being the same as above described. Moreover, as will be apparent to those skilled in the art, the described catheter constructions, are generally useful in providing fluid communication between a body vessel or cavity (including, for example, the spinal canal, the chest cavity, the abdominal cavity and the urinary bladder) and external apparatus.

Iclaim:

1. A catheter, comprising: a body having a bore therethrough and including a hub portion and a trocar portion, said hub portion having a recess therein communicating with said bore and said trocar portion having a sharpened end for piercing insertion into a patient; an elongated flexible tube having a portion extending into said bore in said body and a portion extending outwardly from said body, said tube being slideable in said body to extend beyond the end of said trocar portion and into the patient and to permit withdrawal of said trocar portion from the patient; an enlarged plug secured on said outwardly extending portion of said tube and having a bore therein communicating with the interior of said tube, said plug being seated in said recess in said hub portion when said tube is fully inserted into the patient, and said plug having a vent passage communicating with said bore to permit release of air in said tube when said tube is inserted into the patient and to permit flow of fluid therethrough for indicating insertion of said tube in the patient, the outer end of said vent passage being positioned in said recess when said plug is seated therein for preventing leakage of fluid from said plug; and means adapted to be connected to fluid-communicating apparatus prior to insertion of said trocar portion into the patient for permitting fluid flow between said apparatus and said patient through said tube.

2. A datheter according to claim 1 wherein said means adapted to be connected to said fluid-communicating apparatus includes a passage through said hub, said passage communicating with said vent passage in said plug when said plug is seated in said recess whereby said vent thereupon forms part of the passageway for the flow of fluid between said fluid-communicating apparatus and the patient.

3. A catheter according to claim 2 further comprising a flexible envelope engaging said needle hub and surrounding said plug and said flexible tube in order to maintain same in sterile condition.

4. A catheter according to claim 1 wherein said portion of said tube extending into said body is of greater length than said portion of said tube extending outwardly from said body to maintain sterility of the portion of said tube insertable into the patient.

5. A catheter, comprising: a body having a bore therethrough and including a hub portion and a trocar portion, said hub portion having a recess therein communicating with said bore, said trocar portion having a sharpened end for piercing insertion into a patient; an elongated flexible tube having a portion extending into said bore in said body and a portion extending outwardly from said body, said tube being slidable in said body to extend beyond the end of said trocar portion and into the patient and to permit withdrawal of said trocar portion from the patient, said portion of said tube extending into said body being of greater length than said portion of said tube extending outwardly from said body, and said portion of said tube extending outwardly from said body being uncovered and exposed to unsterile conditions whereas said portion of said tube extending into said body is maintained in a sterile condition by the covering of said last-named portion by said body thereby to maintain sterility of the portion of said tube receivable in the patient; an enlarged member on said outwardly extending portion of said tube, said member being seated in said recess in said hub portion when said tube is fully inserted into the patient; and means adapted to be connected to fluidcommunicating apparatus prior to insertion of said trocar portion into the patient for permitting a fluid flow between said apparatus and said patient through said tube.

6. A catheter according to claim 5 wherein said hub portion comprises a hub member, from which said trocar portion depends, and an extension tube connected to said hub member and extending rearwardly thereof, said recess being provided at the rear of said extension tube.

References Cited UNITED STATES PATENTS 2,829,644 5/ 1958 Anderson 128-221 2,937,643 5/ 1960 Elliot 128-2144 3,055,361 9/1962 Ball ard 128-2144 3,185,152 5/1965 Ring 128-2144 3,335,723 8/1967 Waldman l282l4.4

FOREIGN PATENTS 1,092,011 11/1954 France. 1,087,323 8/1960 Germany.

DALTON L. TRULUCK, Primary Examiner US. Cl. X.R. 128-221; 206-632 

